Impact mitigation is crucial to the stable locomotion of legged robots, especially in high-speed dynamic locomotion. This paper presents a leg locomotion system including the nonlinear active compliance control and the active impedance control for the steel wire transmission-based legged robot. The developed control system enables high-speed dynamic locomotion with excellent impact mitigation and leg position tracking performance, where three strategies are applied. a) The feed-forward controller is designed according to the linear motor-leg model with the information of Coulomb friction and viscous friction. b) Steel wire transmission model-based compensation guarantees ideal virtual spring compliance characteristics. c) Nonlinear active compliance control and active impedance control ensure better impact mitigation performance than linear scheme and guarantee position tracking performance. The proposed control system is verified on a real robot named SCIT Dog and the experiment demonstrates the ideal impact mitigation ability in high-speed dynamic locomotion without any passive spring mechanism.

中文翻译：

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使用非线性主动柔顺控制的钢丝传动动态腿机器人的冲击减轻

减轻冲击对于腿式机器人的稳定运动至关重要，尤其是在高速动态运动中。本文提出了一种包含非线性主动柔顺控制和主动阻抗控制的基于钢丝传动的腿式机器人的腿运动系统。开发的控制系统实现了高速动态运动，具有出色的冲击缓解和腿部位置跟踪性能，其中应用了三种策略。a) 前馈控制器是根据线性电机腿模型设计的，具有库仑摩擦和粘性摩擦的信息。b) 基于钢丝传动模型的补偿保证了理想的虚拟弹簧柔量特性。c) 非线性主动柔顺控制和主动阻抗控制确保比线性方案更好的冲击缓解性能并保证位置跟踪性能。所提出的控制系统在名为 SCIT Dog 的真实机器人上进行了验证，实验证明了在没有任何被动弹簧机构的高速动态运动中理想的冲击缓解能力。